All good advice so far, also I would shoot several shots for each group you shoot so you can be sure to discount flyers. I like to shoot 10 shot groups. Measure each group or save targets and keep a note book with the results. Only change one variable at a time.
all good stuff - also - do not use phony powders in your ML's
standard ball diameters for most commercial .45's will run .440" and .445". These ball diameters are for bores that are .450" or very nearly so.
Much depends on the intended use. For chunk, bench or plank shooting, the .451" and .018" patch will likely work just fine. .454" TO .457" might be even better
if using Teflon-coated patching with wiping between shots.
For trail walks, gentle competition and hunting, a .440" or .445" ball and .018" to .022" patch is likely to be the best. I use water based lubes for target, oils for hunting, as in
Track's Mink Oil or Neetsfoot Oil (not compound) Never use water based nor water soluble oils for hunting. They attract water, do not protect and water will cause cancer in your bore.
Powder charges will be what the rifle wants you to use - do not try to get the gun to work with what YOU want, use what it wants - if you want it to do it's best.
In this case, I'd start at 55gr. 3F or 60gr. 2F and go from there. I checked JoAnne's Fabrics in Yuma when there in December & they had 11 ounce Denim. I did not see 10 ounce.
Either of those will work with .440" or .445". 8 ounce will also work with .445" balls in square rifling. In deeper round bottom rifling, I'd use the 10 ounce with .445" balls.
I personally used 10 ounce denim in my .45 GM barrel with .445" balls. It's accuracy load for 50yards and further was .445" ball, 10 ounce denim and either - 75gr. 3F or 85gr. 2F.
Both of those loads produced just over 2,200fps and shot quite well to 200yards, but also made 1/2", 5-shot groups at 50 yards. Shot without wiping, of course.